1. p53 function and regulation in normal cells and cancer cells
생명시스템학과
종양학 실험실 강 소 미

2. Index Normal cells vs Cancer cells Tumor suppressor genes p53
p53 in normal cells
p53 in cancer cells
Summary

3. Difference between normal cells and cancer cells

4. Uncontrolled cell division

5. Normal cell Malignant cell
Abnormal shape and size
Increased mitotic activity

6. Normal cell Cancer cell
Small, uniformly shaped nuclei
Relatively large cytoplasmic volume
Conformity in cell size and shape
Cells arranged into discrete tissues
May possess differentiated cell structures
Normal presentation of cell surface markers
Lower levels of dividing cells
Cell tissues clearly demarcated
Large, variable shaped nuclei
Relatively small cytoplasmic volume
Variation in cell size and shape
Disorganized arrangement of cells
Loss of normal specialized features
Elevated expression of certain cell markers
Large number of dividing cells
Poorly defined tumor boundaries

7. About tumor suppressor genes..

8. Tumor suppressor genes
Anti-oncogenes
Genes that protect cells from one step on the path to cancer
Normally act to inhibit cell proliferation and tumor development

9. Common human tumor suppressor genes

10. Mechanisms of tumor suppressor genes inactivation
Deletion
Point mutation
Mutation followed by duplication
Loss of heterozygosity
DNA methylation
Post-translational mechanism-binding to DNA viral onco-proteins

11. About p53, one of major tumor suppressor genes..

12. p53 Tumor suppressor genes

13. Major function of p53

14. p53 function and regulation in normal cells..

15. p53, the cellular gate keeper for growth and division

16. p53 regulates cellular redox homeostasis

17. p53 as an integrator of cellular stress

18. In normal cells, the p53 product acts at the G1→S checkpoint preventing entry into S phase if DNA is damaged

19. In normal cells, the p53 product stimulates Apoptosis if DNA damage cannot be repaired
p53 gives an internal signal for apoptosis

20. Regulation of p53 in normal cells
In normal cells, there are low levels of p53 because p53 is targeted for proteasomal degradation
P53 is activated in response to cellular stress, such as biochemical signal, UV radiation, X-rays and toxin

21. Regulation of p53 in normal cells

22. Loss of p53 function and regulation in cancer cells..

23. In cancer cells, mutation occurred in p53
Mutant p53 oncogenic gain of function

25. Regulation of wild and mutant p53 stability in response to stress

26. Mutant p53 signaling in cancer cells

27. In cancer cells, mutant p53 cannot arrest the cell cycle

28. Mutant p53 cannot inhibit abnormal cell division

29. Summary

30. Thank you for listening..